In this paper the most important constraints of the wind sensors for the Martian atmosphere are described, along with an overview of the past successful designs. Practically all the data available today about the Martian surface wind has been measured using hot film anemometry. A novel wind sensor element is described that will be equipping a REMS (remote environment monitoring system) instrument for the MSL rover by NASA. The device is based on four silicon chips coplanarly assembled, embedded inside an electrothermal sigma-delta closed loop, with digital readout. The device has been shown to be able to work at 6mbar pressure in CO2 atmosphere, and to sense winds up to 60 m/s with a 1 second response time. The design and fabrication of a 2D wind sensor has been developed by the authors, and will be mounted in a full 3D structure by a larger research team involving CRISA and CAB